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Results 251 - 300 of 1621
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Sud Dhruv - - 2009
Calibration of fluorescent optical sensors for accurate, quantitative intracellular measurements in vivo suffers from lack of a representative medium that appropriately simulates the molecular complexity of the cytosol. We present a novel protocol for accurate intracellular oxygen sensing via fluorescence lifetime imaging microscopy (FLIM) using cell lysate-FLIM measurements to correct ...
Popa Radu - - 2009
Individual magnetosome-containing magnetic mineral particles (MMP) from magnetotactic bacteria grow rapidly such that only a small fraction (5%) of all magnetosomes contain dwarf (< or =20 nm) MMP. Studies of the developmental stages in the growth of MMP are difficult due to the absence of techniques to separate dwarf from ...
Wang XiaoBing - - 2009
This study is to test the sensitivities of different tumor cells to ultrasound irradiation at the frequency of 2.2 MHz for 60 s duration, and investigate the potential mechanism underlying different sensitivities. Three murine tumor models with distinct aggressiveness (S180, H-22 and EAC) were exposed to ultrasound to evaluate their ...
So Cheung-Wai - - 2010
Photodynamic therapy is a treatment that combines the use of three non-toxic components, viz. photosensitiser, light and oxygen to cause localised oxidative photodamage. In the present study, the antifungal effect of the photosensitiser, BAM-SiPc, an unsymmetrical bisamino phthalocyanine, was investigated. BAM-SiPc was effective in photo-inactivating Candida albicans in a dose-dependent ...
Robinson John M - - 2009
Phagocytic leukocytes, when appropriately stimulated, display a respiratory burst in which they consume oxygen and produce superoxide anions. Superoxide is produced by the phagocyte NADPH-oxidase system which is a multiprotein complex that is dissociated in quiescent cells and is assembled into the functional oxidase following stimulation of these cells. Also ...
Bedogni Barbara B Division of Radiation and Cancer Biology, Stanford University, Stanford, CA, - - 2009
The tissue microenvironment plays a critical role in cell survival and growth and can contribute to cell transformation and tumor development. Cellular interactions with the stroma and with other cells provide key signals that control cellular arrest or division, survival or death, and entrance or exit from a quiescent state. ...
Umekawa Tohru - - 2009
OBJECTIVE To test the hypothesis that exposure of a renal epithelial cell line, NRK52E, to calcium oxalate monohydrate crystals (COM) would up-regulate NADPH oxidase subunit p47(phox), enhance superoxide production and increase monocyte chemoattractant protein-1 (MCP-1) and osteopontin mRNA levels. MATERIALS AND METHODS Confluent cultures of NRK52E cells were exposed to ...
Zhang Rui R Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216, - - 2009
Macula densa cells produce superoxide (O2-) during tubuloglomerular feedback primarily via NAD(P)H oxidase (NOX). The purpose of the present study was to determine NOXs expressed by the macula densa and the role of each one in NaCl-induced O2- production. To identify which isoforms are expressed, we applied single-cell RT-PCR to ...
Yoshii Hanako - - 2009
Oxygen is essential for life, and cells have therefore developed numerous adaptive responses to oxygen change. Here, we examined the difference in oxygen-control functions of human (HE), mouse (ME), and Syrian hamster embryo (SHE) cells cultured under different oxygen conditions (0.5%, 2% and 20%), and also examined whether oxygen tensions ...
Chou Duen-Suey - - 2009
In a previous study, we demonstrated that baicalein induces hydroxyl radical formation in human platelets but the mechanisms are unclear. Herein, we show, using an electron spin resonance technique, that baicalein also induces hydroxyl radical formation in B16F10 melanoma cells in a dose-dependent manner. Baicalein produced superoxide anions in the ...
Guo Shuhong S University of New Mexico Health Sciences Center, Albuquerque, - - 2009
Hypoxia inducible factor 1 (HIF-1) has been suggested to play a critical role in the fate of cells exposed to hypoxic stress. However, the mechanism of HIF-1-regulated cell survival is still not fully understood in ischemic conditions. Redox status is critical for decisions of cell survival, death and differentiation. We ...
Seo Kyo Seong - - 2009
The biochemical oxygen demand (BOD) determination was studied using a novel flow injection analysis (FIA) system with encapsulated Saccharomyces cerevisiae cells and an oxygen electrode and was compared with conventional 5-day BOD tests. S. cerevisiae cells were packed in a calcium alginate capsule at a dry cell weight of 250 ...
Deshpande Rahul Ravi - - 2009
We show the application of a novel optical on-line sensor fixed in spinner flasks for the online monitoring of dissolved O(2) concentrations during mammalian cell growth. Using this sensor that requires only minute changes to the flask to be made, we could determine the volumetric O(2) transfer coefficient as well ...
Chung Woon-Gye - - 2009
Proanthocyanidins (PCs) have been shown to suppress the growth of diverse human cancer cells and are considered as promising additions to the arsenal of chemopreventive phytochemicals. An oligomeric mixture of PCs from hops (Humulus lupulus) significantly decreased cell viability of human colon cancer HT-29 cells in a dose-dependent manner. Hop ...
Molter Timothy W - - 2009
Due to interest in cell population heterogeneity, the development of new technology and methodologies for studying single cells has dramatically increased in recent years. The ideal single cell measurement system would be high throughput for statistical relevance, would measure the most important cellular parameters, and minimize disruption of normal cell ...
Kuimova Marina K - - 2009
Singlet molecular oxygen, O(2)(a(1)Delta(g)), can be created in a single cell from ground-state oxygen, O(2)(X(3)Sigma(g)(-)), upon focused laser irradiation of an intracellular sensitizer. This cytotoxic species can subsequently be detected by its 1270 nm phosphorescence (a(1)Delta(g) --> X(3)Sigma(g)(-)) with subcellular spatial resolution. The singlet oxygen lifetime determines its diffusion distance ...
Wang Ling - - 2009
This study investigated the factors influencing the oxygen metabolism of aortic valve interstitial cells (VICs). Porcine VICs in cell suspension at different passages, and adhered to coverslips at different confluencies, as well as fresh porcine valve leaflets, were incubated in an oxygen respiration chamber at 37 degrees C in Dulbecco's ...
S.L. Ho
The design, fabrication and performance evaluation of a passive direct methanol fuel cell (DMFC) operated at ambient condition with an active area of 7.5 cm&lt;SUP&gt;2 &lt;/SUP&gt;is studied in this research. The fuel cell is air-breathing and passive without any external pumps or auxiliary devices. Oxygen is taken from the surrounding ...
Verklan M Terese - - 2009
Hypoxic-ischemic encephalopathy (HIE) is one of the most important complications found in the newborn period. It is the result of a deprivation of oxygen and glucose to the neural tissue, which may be the result of either hypoxemia or ischemia. Experimental animal research and clinical observations in humans have noted ...
Matsui Satoshi - - 2009
The present study was conducted to investigate the effects of reactive oxygen species (ROS) on the calcification ability of human dental pulp (HDP) cells. HDP cells were treated with 100 mumol/L hydrogen peroxide (H(2)O(2)) for 5 or 10 minutes (5-min ROS group and 10-min ROS group) to investigate the mechanism ...
Maraldi Tullia - - 2009
The mechanism involved in the prosurvival effect of interleukin-3 on the human acute myeloid leukaemia cell line M07e is investigated. A decrease in intracellular reactive oxygen species (ROS) content, glucose transport activity and cell survival was observed in the presence of inhibitors of plasma membrane ROS sources, such as diphenylene ...
Nogawa Hisashi - - 2009
BACKGROUND AND OBJECTIVE: Reactive oxygen species (ROS) play an important role in the pathogenesis of various respiratory diseases. Carbocisteine, a mucoregulatory drug, is used in the treatment of several disease states but little information is available about its scavenger effects on ROS. The present study was designed to examine the ...
Engler Ivan - - 2009
In the nature including the human organism there are 5 reactive oxygen species (ROS): O2, O2-*, O2+*, 1O2, O3 with different electromagnetic characteristics and biological effects. The effects of enrichment of medical oxygen O2 with traces of ROS on various cells were tested in experiments. METHODS: Human embryonic lung fibroblasts ...
Dayan Frédéric - - 2009
Accumulation of HIF-1alpha during normoxic conditions at high cell density has previously been shown to occur and can be used to stabilize HIF-1alpha protein in the absence of a specific anaerobic chamber. However, the impact and origin of this pool of HIF-1alpha, obtained under normoxia, has been underestimated. In this ...
Shaikh Shamim B - - 2009
Exposure to toxins/chemicals is considered to be a significant risk factor in the pathogenesis of Parkinson's disease (PD); one putative chemical is the naturally occurring herbicide rotenone that is now used widely in establishing PD models. We, and others, have shown that chronic low dose rotenone treatment induces excessive accumulation ...
Raclavský V - - 2009
Cryptococcus neoformans was grown in 96-well microtiter plates sealed by foil which is less than 0.01 % permeable to oxygen. On day 14 of the cultivation, we observed peculiar clusters of small droplike daughter cells arranged around < or = 4 % of mother cells. The fact that most of ...
Dat Nguyen Tien - - 2009
Hypoxia-inducible factor-1 (HIF-1) is the central mediator of cellular responses to low oxygen concentrations and vital to many aspects of cancer biology. Bioassay-guided fractionation of the chloroform-soluble extracts of Morus species using a hypoxia response element (HRE)-dependent reporter assay led to identification of six benzofurans (1-6) and two chalcone-derived Diels-Alder ...
Warnke Christian - - 2009
The metabolic dynamics of yeast cells is controlled by electric pulses delivered through a spatially extended yeast cell/Au electrode interface. Concomitant with voltage pulses, oxygen is generated electrolytically at the electrode surface and delivered to the cells. The generation of oxygen was investigated in dependence of the applied voltage, width ...
Jiang Fan - - 2009
NADPH oxidase-derived reactive oxygen species are implicated in apoptosis in certain kidney cells. On the other hand, NADPH oxidase is also involved in promoting cell proliferation in the kidney. The two faces of NADPH oxidase in these situations prompt us to argue that the role of this enzyme in various ...
Cossarizza Andrea - - 2009
Reactive oxygen species (ROS) are continuously produced in the cell as a consequence of aerobic metabolism, and are controlled by several antioxidant mechanisms. An accurate measurement of ROS is essential to evaluate the redox status of the cell, or the effects of molecules with the pro-oxidant or antioxidant activity. Here ...
Lluis Josep M - - 2009
Hypoxia-mediated HIF-1alpha stabilization and NF-kappaB activation play a key role in carcinogenesis by fostering cancer cell survival, angiogenesis and tumor invasion. Gangliosides are integral components of biological membranes with an increasingly recognized role as signaling intermediates. In particular, ganglioside GD3 has been characterized as a proapoptotic lipid effector by promoting ...
Desai Nisarg R - - 2009
Hazardous health effects stemming from exposure to radiofrequency electromagnetic waves (RF-EMW) emitted from cell phones have been reported in the literature. However, the cellular target of RF-EMW is still controversial. This review identifies the plasma membrane as a target of RF-EMW. In addition, the effects of RF-EMW on plasma membrane ...
Pistollato Francesca - - 2009
Glioblastoma multiforme (GBM) is one of most common and still poorly treated primary brain tumors. In search for new therapeutic approaches, Bone Morphogenetic Proteins (BMPs) induce astroglial commitment in GBM-derived cells in vitro. However, we recently suggested that hypoxia, which is characteristic of the brain niche where GBM reside, strongly ...
Weston Mark A - - 2009
Fluorescence photobleaching, photodynamic therapy (PDT) oxygen consumption and clonogenic cell survival were investigated during 2-(1-hexyloxethyl)-2-devinyl pyropheophoribde-a (HPPH) PDT of MAT-LyLu cells in vitro. Cells were incubated with HPPH concentrations of 0.24, 1.2, 3.6 or 12 microm for 4 h and then treated with 650 nm light under oxygenated and hypoxic ...
Semenza Gregg L - - 2008
Intratumoral hypoxia increases invasion and metastasis through multiple mechanisms, including changes in gene expression that are mediated by hypoxia-inducible factor 1. In hypoxic colon cancer cells, hypoxia-inducible factor 1 inhibits the expression of CD151, a cell surface molecule that normally tethers epithelial cells to the basement membrane, which may promote ...
Seshareddy, Kiran Babu
Wharton's jelly is a non-controversial source of mesenchymal stromal cells. Isolation of the cells is non-invasive and painless. The cells have been shown to have a wide array of therapeutic applications. They have improved symptoms when transplanted in a variety of animal disease models, can be used in tissue engineering ...
Bulgakov Victor P - - 2008
It is known that expression of the Agrobacterium rhizogenes rolC gene in transformed plant cells causes defense-like reactions, such as increased phytoalexin production and expression of pathogenesis-related proteins. In the present study, we examined whether this phenomenon is associated with increased production of reactive oxygen species (ROS). Single-cell assays based ...
Jurkovicova Dana - - 2008
Hypoxia is a state of insufficient oxygen supply of the tissue or cell. Kidney tissue is highly sensitive to oxygen deprivation and easily develops renal ischemic injury. Calcium transporters very sensitively react to oxygen deficiency. We investigated whether hypoxia affects the gene expression of intracellular calcium transporters in the intact ...
Cárdenas Luis - - 2008
Reactive oxygen species (ROS) are involved in supporting polar growth in pollen tubes, fucoid cells and root hair cells. However, there is limited evidence showing ROS changes during the earliest stages of the interaction between legume roots and rhizobia. We recently reported using Phaseolus vulgaris as a model system, the ...
Strianese Maria - - 2009
Fluorescently labeled hemocyanin has been previously proposed as an oxygen sensor. In this study, we explored the efficacy of this biosensor for monitoring the biological oxygen consumption of bacteria and its use in testing bacterial cell growth and viability of Escherichia coli, Pseudomonas aeruginosa, Paracoccus denitrificans, and Staphylococcus simulans. Using ...
Zhu Ying - - 2008
Recent developments in high cell density and high productivity fed-batch animal cell cultures have placed a high demand on oxygenation and carbon dioxide removal in bioreactors. The high oxygen demand is often met by increasing agitation and sparging rates of air/O2 in the bioreactors. However, as we demonstrate in this ...
Díaz Belén - - 2008
Inorganic nanoparticles (NPs) show great potential for medicinal therapy. However, biocompatibility studies are essential to determine if they are safe. Here, five different NPs are compared for their cytotoxicity, internalization, aggregation in medium, and reactive oxygen species (ROS) production, using tumoral and normal human blood cells. Differences depending on the ...
Lyon Delina Y - - 2008
Buckminsterfullerene (C60) can form water suspensions (nC60) that exert toxic effects. While reactive oxygen species (ROS) generation has been implicated as the mechanism for mammalian cytotoxicity, we propose that nC60 exerts ROS-independent oxidative stress in bacteria, with evidence of protein oxidation, changes in cell membrane potential, and interruption of cellular ...
López-Barneo J - - 2008
The carotid body (CB) is a neural crest-derived organ whose major function is to sense changes in arterial oxygen tension to elicit hyperventilation in hypoxia. The CB is composed of clusters of neuron-like glomus, or type-I, cells enveloped by glia-like sustentacular, or type-II, cells. Responsiveness of CB to acute hypoxia ...
Liu Qing - - 2008
Oxidative damage is an important mechanism in X-ray-induced cell death. Radiolysis of water molecules is a source of reactive oxygen species (ROS) that contribute to X-ray-induced cell death. In this study, we showed by ROS detection and a cell survival assay that NADPH oxidase has a very important role in ...
Eblin K E KE Department of Pharmacology and Toxicology, University of Arizona, USA. - - 2009
UROtsa cells exposed to 50 nM monomethylarsonous acid [MMA(III)] for 52 wk (MSC52) achieved hyperproliferation, anchorage independent growth, and enhanced tumorgenicity. MMA(III) has been shown to induce reactive oxygen species (ROS), which can lead to activation of signaling cascades causing stress-related proliferation of cells and even cellular transformation. Previous research ...
Firth James D - - 2008
Chymase is a chymotrypsin-like serine protease predominantly produced by mast cells. In this study, human cutaneous and gingival keratinocytes, ovary surface epithelia, and a porcine epithelial cell line were assayed by homology-based cloning, and the amplified DNA fragment was identified as a chymase. In vitro, chymase could not be induced ...
Qian Xia - - 2009
1. Erlotinib, a small-molecule epidermal growth factor receptor-tyrosine kinase (EGFR-TK) inhibitor, has been approved for the management of advanced non-small cell lung cancer. The aim of the present study was to investigate whether erlotinib exerts potent antitumour activities through the reactive oxygen species (ROS)-c-Jun N-terminal kinase (JNK) pathway in the ...
Dragavon Joe - - 2008
The development of a cellular isolation system (CIS) that enables the monitoring of single-cell oxygen consumption rates in real time is presented. The CIS was developed through a multidisciplinary effort within the Microscale Life Sciences Center (MLSC) at the University of Washington. The system comprises arrays of microwells containing Pt-porphyrin-embedded ...
Bernard Yohann - - 2008
Vascular cells and leukocytes, involved in the development of atherosclerosis, produce cytokines and/or reactive oxygen species (ROS) and matrix metalloproteinases (MMPs) implicated in cell mobility. We investigated by co-culture experiments the effects of human coronary smooth muscle cells (HCSMC) on MMPs characteristics and mobility of neutrophil-like dimethyl sulfoxide-differentiated HL60 cells ...
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